v2.4.0.8
Debt (Fair Value of Debt) (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Portion at Fair Value Measurement [Member]
   
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Notes Payable, Fair Value Disclosure $ 5,317 $ 5,863
Notes Payable, Other Payables, Disclosure 1,772 [1] 1,599 [1]
Subsidiaries Term Loan 1,179 0
Loans Payable, Fair Value Disclosure 2,845 2,489
Subsidiaries Notes Disclosure 0 1,075
Debt Excluding Capital Leases 11,113 11,026
Reported Value Measurement [Member]
   
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Notes Payable, Fair Value Disclosure 4,989 5,303
Notes Payable, Other Payables, Disclosure 1,766 [1] 1,629 [1]
Subsidiaries Term Loan 1,191 0
Loans Payable, Fair Value Disclosure 2,828 2,463
Subsidiaries Notes Disclosure 0 978
Debt Excluding Capital Leases $ 10,774 $ 10,373
[1] Excludes a lease that is accounted for as a failed sale-leaseback transaction under U.S. GAAP.